Sustainable Development

Reedbed Sewage Treatment

What is a reedbed?

A reedbed is a sewage treatment system which is constructed after a septic tank to improve the cleanliness of septic tank discharges. Some industrial effluents can also be treated by reedbed systems. A reedbed is usually a shallow, rectangular excavation infilled with gravel. The gravel is then planted with the common reed, Phragmites australis. After several months the reeds grow to about 150cm tall to form a dense, green cover, blending the reedbed into its surroundings.

How does a reedbed work?

The reeds planted in the gravel supply, via their roots, oxygen to bacteria that live in the gravel. The bacteria clean the sewage allowing treated, clean water to be discharged to a water course without harm to the environment and wildlife.

Why user reedbeds?

A septic tank and reedbed system is the simplest and cheapest form of sewage treatment available to rural populations. Reedbeds allow developments to be sited where conventional soakaway systems are not suitable. Reedbeds require very little maintenance after their first year of operation and have almost no running costs. Reedbeds provide the additional benefits of a landscaped feature and a habitat for insects and amphibians.